According to Gertrude Stein, “A rose is a rose is a rose,” but new research indicates that might not be the case when it comes to the rose’s scent. Researchers from the Monell Center and collaborating institutions have found that as much as 30 percent of the large array of human olfactory receptor differs between any two individuals.
This substantial variation is in turn reflected by variability in how each person perceives odors.
Humans have about 400 different types of specialized sensors, known as olfactory receptor proteins, that somehow work together to detect a large variety of odors.
“Understanding how this huge array of receptors encodes odors is a challenging task,” says study lead author Joel Mainland, PhD, a molecular biologist at Monell. “The activation pattern of these 400 receptors encodes both the intensity of an odor and the quality – for example, whether it smells like vanilla or smoke – for the tens of thousands of different odors that represent everything we smell.
Right now, nobody knows how the activity patterns are translated into a signal that our brain registers as the odor.”
Adding to the complexity of the problem, the underlying amino acid sequence can vary slightly for each of the 400 receptor proteins, resulting in one or more variants for each of the receptors. Each receptor variant responds to odors in a slightly different way and the variants are distributed across individuals such that nearly everyone has a unique combination of olfactory receptors.
To gain a better understanding of the extent of olfactory receptor variation and how this impacts human odor perception, Mainland and his collaborators used a combination of high-throughput assays to measure how single receptors and individual humans respond to odors. The results, published in Nature Neuroscience, provide a critical step towards understanding how olfactory receptors encode the intensity, pleasantness and quality of odor molecules.
The researchers first cloned 511 known variants of human olfactory receptors and embedded them in host cells that are easy to grow in the laboratory. The next step was to measure whether each receptor variant responded to a panel of 73 different odor molecules. This process identified 28 receptor variants that responded to at least one of the odor molecules.
Drilling down, the researchers next examined the DNA of 16 olfactory receptor genes, discovering considerable variation within the genes for discrete receptors.
Using sophisticated mathematical modeling to extrapolate from these results, Mainland predicts that the olfactory receptors of any two individuals differ by about 30 percent. This means that for any two randomly chosen individuals, approximately 140 of their 400 olfactory receptors will differ in how they respond to odor molecules.
To understand how variation in a single olfactory receptor affects odor perception, the researchers studied responses to odors in individuals having different variants of a receptor known as OR10G4. They found that variations in the OR10G4 receptor were related to how people perceive the intensity and pleasantness of guaiacol, a molecule that often is described as having a ‘smoky’ characteristic.
Moving forward, a current study is relating the olfactory receptor repertoire of hundreds of people with how those people respond to odors. The data will enable the researchers to identify additional examples of how changes in individual receptors affect olfactory perception.
“The long-term goal is to figure out how the receptors encode odor molecules well enough that we can actually create any odor we want by manipulating the receptors directly,” said Mainland. “In essence, this would allow us to ‘digitize’ olfaction.”
Source: Monell Chemical Senses Center
Accelerated Resolution Therapy, or ART, is a brief, safe, and effective treatment for combat-related symptoms of post-traumatic stress disorder (PTSD) among veterans and U.S. service members, researchers at University of South Florida College of Nursing report in a new study. They found this newer treatment — a combination of evidence-based psychotherapies and use of eye movements — was shorter and more likely to be completed, than conventional therapies formally endorsed by the U.S. Department of Defense and the Veterans Administration.
The findings appear online today in advance of December’s print issue of Military Medicine, the international journal of AMSUS.
Kevin Kip, PhD, FAHA, professor and executive director for the Research Center at the USF College of Nursing, led the team of scientists and clinicians who conducted the first randomized controlled trial of ART in a military population. The trial enrolled 57 service members and veterans, primarily from the Tampa Bay area.
“Based on this trial and an earlier study completed at the USF College of Nursing, we believe that accelerated resolution therapy may provide the quickest way to effectively and safely treat post-traumatic stress disorder,” Dr. Kip said. “Our goal is to obtain enough evidence and interest to warrant classifying ART as a potential first-line treatment for PTSD among both civilian and military personnel.”
“Dr. Kip’s work on this project has been phenomenal,” said Dianne Morrison-Beedy, PhD, RN, WHNP-BC, FNAP, FAANP, FAAN, senior associate vice president of USF Health, and dean of the College of Nursing. “ART has been a cornerstone of RESTORE LIVES at USF Nursing as we continue developing research and education to advance the health care received by veterans, service members and their families.”
ART works in two phases to alleviate psychological trauma symptoms and related disorders such as depression and anxiety.
The patient first visualizes in his or her mind a prior traumatic experience which typically elicits uncomfortable physiological sensations like tightness of the chest, increased heart rate and sweating. Then, through talk therapy and a series of rapid left-to-right eye movements in which the patient follows the clinician’s hand back and forth, the sensations are minimized. In the second phase, and with similar clinician input, the patient “replaces” the distressing images they have seen with positive ones in a way that the original distressing images can no longer be accessed. ART is delivered in two to five one-hour sessions, requires no homework, and no written or verbal recall of the traumatic experience.
“Through this therapy, we’re able to quiet down and separate physiological symptoms that come with re-envisioning a traumatic experience,” Dr. Kip said. “We can also alter or replace the traumatic images and add positive material to them. We are changing how images are remembered in the brain.”
It worked well for Brian Anderson, a former Green Beret, 10-year Army veteran and director of the Pasco County Veteran Services and Stand Down program. He had tried an endorsed first-line PTSD treatment known as prolonged exposure therapy, which was very lengthy and worked for a while, but then symptoms like hyper-vigilance returned.
“ART changed my life,” Anderson said. “This brief therapy took the bad memories that constantly resurfaced and put them in the proper order or long-term storage; it was almost like I was thinking about a time in history. As a veteran, I would much rather go through a therapy that works, in only a few sessions, than sit through intensive and grueling sessions that last as long as 16 weeks.”
In this study, researchers compared ART to a non-therapeutic PTSD treatment called attention control (AC) regimen. Clinicians treated half of the 57 study participants (29) with ART, and the other half (28) received AC, which consisted of either physical fitness assessment and planning or career assessment and planning. After initial treatment, both groups received a three-month follow-up assessment.
“Before and after these interventions, we compared the response analyzing reductions in PTSD symptoms, depression and anxiety, and the results were very impressive,” Dr. Kip said. “In an average of less than four ART sessions, participants had very substantially reduced symptoms of PTSD, while those who received AC did not.”
After the AC regimen, all veterans had the opportunity to receive ART, and in the full study, 94 percent completed treatment. Favorable results persisted at three months.
The USF College of Nursing recently began its fourth and largest ART study. Researchers will recruit 200 veterans and service members suffering from PTSD, including a high representation of those who were sexually abused or previously treated with other PTSD therapies. They will also study the cost-effectiveness of ART, and further examine how and why the therapy works.
PTSD is a prevalent, disabling disorder that can emerge following a life-threatening event or traumatic experience. Those experiences create chronic symptoms such as flashbacks, nightmares, sleep disturbances, mood swings, and loss of interest in life. According to PTSD Foundation of America, one in three troops returning from combat suffers PTSD symptoms, although less than 40 percent seek help. The organization also reports that at least five active duty military members attempt suicide every day.
“Accelerated resolution therapy is giving hope to many veterans who felt like they had no hope,” said Lt. Col. (Ret.)Lawrence A. Braue, EdD, director of the USF Office of Veterans Services. “I look forward to the day when this treatment is widely available across the country. USF College of Nursing faculty and staff genuinely care about our veterans, and that means the world to any veteran.
Source: University of South Florida Tampa
Mothers get all the attention. But a study led by McGill researcher Sarah Kimmins suggests that the father’s diet before conception may play an equally important role in the health of their offspring. It also raises concerns about the long-term effects of current Western diets and of food insecurity.
The research focused on vitamin B9, also called folate, which is found in a range of green leafy vegetables, cereals, fruit and meats. It is well known that in order to prevent miscarriages and birth defects mothers need to get adequate amounts of folate in their diet. But the way that a father’s diet can influence the health and development of their offspring has received almost no attention. Now research from the Kimmins group shows for the first time that the father’s folate levels may be just as important to the development and health of their offspring as are those of the mother. Indeed, the study suggests that fathers should pay as much attention to their lifestyle and diet before they set out to conceive a child as mothers do.
“Despite the fact that folic acid is now added to a variety of foods, fathers who are eating high-fat, fast food diets or who are obese may not be able to use or metabolize folate in the same way as those with adequate levels of the vitamin,” says Kimmins. “People who live in the Canadian North or in other parts of the world where there is food insecurity may also be particularly at risk for folate deficiency. And we now know that this information will be passed on from the father to the embryo with consequences that may be quite serious.”
The researchers arrived at this conclusion by working with mice, and comparing the offspring of fathers with insufficient folate in their diets with the offspring of fathers whose diets contained sufficient levels of the vitamin. They found that paternal folate deficiency was associated with an increase in birth defects of various kinds in the offspring, compared to the offspring of mice whose fathers were fed a diet with sufficient folate.
“We were very surprised to see that there was an almost 30 per cent increase in birth defects in the litters sired by fathers whose levels of folates were insufficient,” said Dr. Romain Lambrot, of McGill’s Dept. of Animal Science, one of the researchers who worked on the study. “We saw some pretty severe skeletal abnormalities that included both cranio-facial and spinal deformities.”
The research from the Kimmins’ group shows that there are regions of the sperm epigenome that are sensitive to life experience and particularly to diet. And that this information is in turn transferred to a so-called epigenomic map that influences development and may also influence metabolism and disease in the offspring in the long-term. (The epigenome is like a switch, which is affected by environmental cues, and is involved in many diseases including cancer and diabetes. The epigenome influences the way that genes are turned on or off, and hence how heritable information gets passed along).
Although it has been known for some time that there is a massive erasure and re-establishment that takes place in the epigenome as the sperm develops, this study now shows that along with the developmental map, the sperm also carries a memory of the father’s environment and possibly even of his diet and lifestyle choices.
“Our research suggests that fathers need to think about what they put in their mouths, what they smoke and what they drink and remember they are caretakers of generations to come,” said Kimmins. “If all goes as we hope, our next step will be to work with collaborators at a fertility clinic so that we can start assessing the links in men between diet, being overweight and how this information relates to the health of their children.”
Source: McGill University
After a traumatic experience, the details we remember surrounding the event are sometimes foggy. According to a new study in the Journal of Consumer Research, consumers remember the least when they feel the most threatened.
“We are looking to identify the factors that contribute to memory impairment,” write authors Amy N. Dalton (Hong Kong University of Science and Technology) and Li Huang (University of South Carolina). “In response to threats against their social identity, people will try to preserve or protect the group they identify with.”
One mental strategy threatened people use is what the authors term “motivated forgetting.” In other words, to cope with trauma, the human brain fails to remember details associated with the event. The authors explain that motivated forgetting often occurs when people feel threatened about their gender, race, or ethnic group.
Consider an advertisement for breast cancer prevention. If the ad focuses on a woman’s vulnerability to the disease, she may feel more vulnerable to the disease and not remember the prevention message at all.
Across four studies and testing a number of variables, the researchers examined how (and if) negative memories are encoded in short- and long-term memory. Their findings show that people are less likely to remember an advertisement if they feel threatened at the same time. For example, students who read a newspaper article about how their university is underperforming were less likely to remember an ad offering a discount at the campus bookstore than students who read an unrelated (non-threatening) article.
Consider a special promotion offered to fans of a local sports team at a sports bar. If the team is having a bad season, dedicated fans may forget about the promotion and take their business elsewhere.
“Social-identity linked marketing is common nowadays and most work on the topic has examined factors like product or brand preference, but not memory. Because memory drives most consumer decisions, our research can help brands identify which factors can cause impairment,” the authors conclude.
New psychology research, which could have important public health implications for alleviating some side effects of antidepressants, shows that engaging in exercise at the right time significantly improves sexual functioning in women who are taking the antidepressants.
The study, published online in Depression and Anxiety, shows that sexual dysfunction can be effectively treated with an inexpensive, non-invasive prescription of moderately intense workouts.
“These findings have important implications for public health, as exercise as a treatment for sexual side effects is accessible, cheap and does not add to burden of care,” says Tierney Lorenz, an Indiana University post-doctoral research fellow who conducted the study at The University of Texas at Austin with Psychology Professor Cindy Meston.
The researchers recruited 52 women who reported sexual side effects from antidepressants. During the first three weeks of the study, the participants engaged in sexual activity with no exercise. In the second experiment, the participants completed either three weeks of exercise immediately before sexual activity, or three weeks of exercise not timed to it. They all also engaged in sexual activity and 30 minutes of strength training and cardio exercise three times a week. The two groups then reversed roles in the last experiment. Women who exercised regularly were asked to add three extra sessions to their workout routines.
The results showed that 30 minutes of exercise just before intercourse can reduce the effect of the libido-dulling drugs. They were based on the participants’ self-reported assessments of their sexual functioning, satisfaction and psychological health before and after each experiment. They also reported each sexual event in online diaries.
According to the findings, committing to a regular exercise routine improved orgasm function in all women. However, those who exercised immediately before sex experienced significantly stronger libidos and overall improvements in sexual functioning.
Moderately intense exercise activates the sympathetic nervous system, which facilitates blood flow to the genital region. Antidepressants have been shown to depress this system. Scheduling regular sexual activity and exercise may be an effective tool for alleviating these adverse side effects, Lorenz says.
“Considering the wide prevalence of antidepressant sexual side effects and the dearth of treatment options for those experiencing these distressing effects, this is an important step in treating sexual dysfunction among women who are taking antidepressants,” Lorenz says.
Source: The University of Texas at Austin
Autism spectrum disorder (ASD) is diagnosed when individuals exhibit characteristic behaviors that include repetitive actions, decreased social interactions, and impaired communication. Curiously, many individuals with ASD also suffer from gastrointestinal (GI) issues, such as abdominal cramps and constipation.
Using the co-occurrence of brain and gut problems in ASD as their guide, researchers at the California Institute Technology (Caltech) are investigating a potentially transformative new therapy for autism and other neurodevelopmental disorders.
The gut microbiota—the community of bacteria that populate the human GI tract—previously has been shown to influence social and emotional behavior, but the Caltech research, published online in the December 5 issue of the journal Cell, is the first to demonstrate that changes in these gut bacteria can influence autism-like behaviors in a mouse model.
“Traditional research has studied autism as a genetic disorder and a disorder of the brain, but our work shows that gut bacteria may contribute to ASD-like symptoms in ways that were previously unappreciated,” says Professor of Biology Sarkis K. Mazmanian. “Gut physiology appears to have effects on what are currently presumed to be brain functions.”
To study this gut–microbiota–brain interaction, the researchers used a mouse model of autism previously developed at Caltech in the laboratory of Paul H. Patterson, the Anne P. and Benjamin F. Biaggini Professor of Biological Sciences. In humans, having a severe viral infection raises the risk that a pregnant woman will give birth to a child with autism. Patterson and his lab reproduced the effect in mice using a viral mimic that triggers an infection-like immune response in the mother and produces the core behavioral symptoms associated with autism in the offspring.
In the new Cell study, Mazmanian, Patterson, and their colleagues found that the “autistic” offspring of immune-activated pregnant mice also exhibited GI abnormalities. In particular, the GI tracts of autistic-like mice were “leaky,” which means that they allow material to pass through the intestinal wall and into the bloodstream. This characteristic, known as intestinal permeability, has been reported in some autistic individuals. “To our knowledge, this is the first report of an animal model for autism with comorbid GI dysfunction,” says Elaine Hsiao, a senior research fellow at Caltech and the first author on the study.
To see whether these GI symptoms actually influenced the autism-like behaviors, the researchers treated the mice with Bacteroides fragilis, a bacterium that has been used as an experimental probiotic therapy in animal models of GI disorders.
The result? The leaky gut was corrected.
In addition, observations of the treated mice showed that their behavior had changed. In particular, they were more likely to communicate with other mice, had reduced anxiety, and were less likely to engage in a repetitive digging behavior.
“The B. fragilis treatment alleviates GI problems in the mouse model and also improves some of the main behavioral symptoms,” Hsiao says. “This suggests that GI problems could contribute to particular symptoms in neurodevelopmental disorders.”
With the help of clinical collaborators, the researchers are now planning a trial to test the probiotic treatment on the behavioral symptoms of human autism. The trial should begin within the next year or two, says Patterson.
“This probiotic treatment is postnatal, which means that the mother has already experienced the immune challenge, and, as a result, the growing fetuses have already started down a different developmental path,” Patterson says. “In this study, we can provide a treatment after the offspring have been born that can help improve certain behaviors. I think that’s a powerful part of the story.”
The researchers stress that much work is still needed to develop an effective and reliable probiotic therapy for human autism—in part because there are both genetic and environmental contributions to the disorder, and because the immune-challenged mother in the mouse model reproduces only the environmental component.
“Autism is such a heterogeneous disorder that the ratio between genetic and environmental contributions could be different in each individual,” Mazmanian says. “Even if B. fragilis ameliorates some of the symptoms associated with autism, I would be surprised if it’s a universal therapy—it probably won’t work for every single case.”
The Caltech team proposes that particular beneficial bugs are intimately involved in regulating the release of metabolic products (or metabolites) from the gut into the bloodstream. Indeed, the researchers found that in the leaky intestinal wall of the autistic-like mice, certain metabolites that were modulated by microbes could both easily enter the circulation and affect particular behaviors.
“I think our results may someday transform the way people view possible causes and potential treatments for autism,” Mazmanian says.
The study identifies five healthy behaviours as being integral to having the best chance of leading a disease-free lifestyle: taking regular exercise, non-smoking, a low bodyweight, a healthy diet and a low alcohol intake.
The people who consistently followed four or five of these behaviours experienced a 60 per cent decline in dementia and cognitive decline – with exercise being the strongest mitigating factor – as well as 70 per cent fewer instances of diabetes, heart disease and stroke, compared with people who followed none.
“The size of reduction in the instance of disease owing to these simple healthy steps has really amazed us and is of enormous importance in an aging population,” said Principle Investigator Professor Peter Elwood from Cardiff University’s School of Medicine. “What the research shows is that following a healthy lifestyle confers surprisingly large benefits to health – healthy behaviours have a far more beneficial effect than any medical treatment or preventative procedure.
“Taking up and following a healthy lifestyle is however the responsibility of the individual him or herself. Sadly, the evidence from this study shows that very few people follow a fully healthy lifestyle. Furthermore, our findings reveal that while the number of people who smoke has gone down since the study started, the number of people leading a fully healthy lifestyle has not changed,” he added.
Recent surveys indicate that less than one per cent of people in Wales follow a completely healthy lifestyle, based on the five recommended behaviours, and that five per cent of the population follow none of the healthy behaviours; roughly equating to a city with a population the size of Swansea (240,000).
Professor Elwood continued: “If the men had been urged to adopt just one additional healthy behaviour at the start of the study 35 years ago, and if only half of them complied, then during the ensuing 35 years there would have been a 13 per cent reduction in dementia, a 12 per cent drop in diabetes, six per cent less vascular disease and a five per cent reduction in deaths.”
The Caerphilly Cohort Study recorded the healthy behaviours of 2,235 men aged 45-59 in Caerphilly, South Wales. The study had multiple aims and has been the basis for over 400 research papers in the medical press. One of the most important aims was to examine the relationship between healthy lifestyles, chronic disease and cognitive decline over a 35-year period; and to monitor changes in the take-up of healthy behaviours.
Dr Doug Brown, Director of Research and Development at the Alzheimer’s Society, said: “We have known for some time that what is good for your heart is also good for your head, and this study provides more evidence to show that healthy living could significantly reduce the chances of developing dementia. These large, longitudinal studies are expensive and complicated to run, but are essential to understand how dementia can be prevented. We are calling on the G8 Summit next week to commit to greater funding of important studies such as this one which give us hope for reducing the impact of dementia in the future.”
Christopher Allen, Senior Cardiac Nurse at the British Heart Foundation, which part-funded the study, said: “The results of this study overwhelmingly support the notion that adopting a healthy lifestyle reduces your risk of cardiovascular disease and dementia. These findings will hopefully go a long way in encouraging people to carefully consider their lifestyle and how it will impact on their health in later years.”
Unhealthy living has accounted for around 10 per cent of the costs of the NHS in Wales since the study first started, while the annual expenditure on prevention and public health services in Wales is estimated to have been £280M.
Today, smartphones are central to college students’ lives, keeping them constantly connected with friends, family and the Internet. Students’ cell phones are rarely out of reach whether the setting is a college classroom, library, recreational center, cafeteria or dorm room. As cell phone use continues to increase, it is worth considering whether use of the device is related to measurable outcomes important for student success, such as academic performance, anxiety and happiness.
Kent State University researchers Andrew Lepp, Ph.D., Jacob Barkley, Ph.D., and Aryn Karpinski, Ph.D., all faculty members in the university’s College of Education, Health and Human Services, surveyed more than 500 university students. Daily cell phone use was recorded along with a clinical measure of anxiety and each student’s level of satisfaction with their own life, or in other words happiness. Finally, all participants allowed the researchers to access their official university records in order to retrieve their actual, cumulative college grade point average (GPA). All students surveyed were undergraduate students and were equally distributed by class (freshman, sophomore, junior and senior). In addition, 82 different, self-reported majors were represented.
Results of the analysis showed that cell phone use was negatively related to GPA and positively related to anxiety. Following this, GPA was positively related to happiness while anxiety was negatively related to happiness. Thus, for the population studied, high frequency cell phone users tended to have lower GPA, higher anxiety, and lower satisfaction with life (happiness) relative to their peers who used the cell phone less often. The statistical model illustrating these relationships was highly significant.
Earlier this year, a team led by Lepp and Barkley also identified a negative relationship between cell phone use and cardiorespiratory fitness. Taken as a whole, these results suggest that students should be encouraged to monitor their cell phone use and reflect upon it critically so that it is not detrimental to their academic performance, mental and physical health, and overall well-being or happiness.
Source: Kent State
With evidence growing that meditation can have beneficial health effects, scientists have sought to understand how these practices physically affect the body.
A new study by researchers in Wisconsin, Spain, and France reports the first evidence of specific molecular changes in the body following a period of mindfulness meditation.
The study investigated the effects of a day of intensive mindfulness practice in a group of experienced meditators, compared to a group of untrained control subjects who engaged in quiet non-meditative activities. After eight hours of mindfulness practice, the meditators showed a range of genetic and molecular differences, including altered levels of gene-regulating machinery and reduced levels of pro-inflammatory genes, which in turn correlated with faster physical recovery from a stressful situation.
“To the best of our knowledge, this is the first paper that shows rapid alterations in gene expression within subjects associated with mindfulness meditation practice,” says study author Richard J. Davidson, founder of the Center for Investigating Healthy Minds and the William James and Vilas Professor of Psychology and Psychiatry at the University of Wisconsin-Madison.
“Most interestingly, the changes were observed in genes that are the current targets of anti-inflammatory and analgesic drugs,” says Perla Kaliman, first author of the article and a researcher at the Institute of Biomedical Research of Barcelona, Spain (IIBB-CSIC-IDIBAPS), where the molecular analyses were conducted.
The study was published in the journal Psychoneuroendocrinology.
Mindfulness-based trainings have shown beneficial effects on inflammatory disorders in prior clinical studies and are endorsed by the American Heart Association as a preventative intervention. The new results provide a possible biological mechanism for therapeutic effects.
The results show a down-regulation of genes that have been implicated in inflammation. The affected genes include the pro-inflammatory genes RIPK2 and COX2 as well as several histone deacetylase (HDAC) genes, which regulate the activity of other genes epigenetically by removing a type of chemical tag. What’s more, the extent to which some of those genes were downregulated was associated with faster cortisol recovery to a social stress test involving an impromptu speech and tasks requiring mental calculations performed in front of an audience and video camera.
Perhaps surprisingly, the researchers say, there was no difference in the tested genes between the two groups of people at the start of the study. The observed effects were seen only in the meditators following mindfulness practice. In addition, several other DNA-modifying genes showed no differences between groups, suggesting that the mindfulness practice specifically affected certain regulatory pathways.
However, it is important to note that the study was not designed to distinguish any effects of long-term meditation training from those of a single day of practice. Instead, the key result is that meditators experienced genetic changes following mindfulness practice that were not seen in the non-meditating group after other quiet activities — an outcome providing proof of principle that mindfulness practice can lead to epigenetic alterations of the genome.
Previous studies in rodents and in people have shown dynamic epigenetic responses to physical stimuli such as stress, diet, or exercise within just a few hours.
“Our genes are quite dynamic in their expression and these results suggest that the calmness of our mind can actually have a potential influence on their expression,” Davidson says.
“The regulation of HDACs and inflammatory pathways may represent some of the mechanisms underlying the therapeutic potential of mindfulness-based interventions,” Kaliman says. “Our findings set the foundation for future studies to further assess meditation strategies for the treatment of chronic inflammatory conditions.”